ATS feeder question

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twinman

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Is it permissible to have an ATS energized as follows?

Normal feed is to be connected to the utility service (w/o standby emergency power) energizing building in which load is located.

Emergency feed is to be connected to the standby emergency generator utilized to back-up an adjacent building which is served by a separate utility service.

Both buildings are separately metered, but owned by one entity.

If permissible, are there any special requirements, such as, tagging, etc, required?

Reference to the Code sections would be appreciated.

Thank you
 
Permissible. You need to read Art 700, 700.8 in regard to signs.
 
twinman said:
Is it permissible to have an ATS energized as follows?

Normal feed is to be connected to the utility service (w/o standby emergency power) energizing building in which load is located.

Emergency feed is to be connected to the standby emergency generator utilized to back-up an adjacent building which is served by a separate utility service.

Both buildings are separately metered, but owned by one entity.

If permissible, are there any special requirements, such as, tagging, etc, required?

Reference to the Code sections would be appreciated.

Thank you
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If you are saying what I think you are saying then no. look at 702.6
If you are saying is you want to utility feed a ATS from one service to supply another building that has a separate service then how will you keep from back feeding on the utility?
 
ceb58 said:
If you are saying what I think you are saying then no. look at 702.6
If you are saying is you want to utility feed a ATS from one service to supply another building that has a separate service then how will you keep from back feeding on the utility?
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He wasn't real clear on that, was he?

The impression I got is that he wants to use one generator as an alternate power source connected to two service-supplied systems via an ATS for each system... but now I'm unsure :cool:
 
Smart $ said:
He wasn't real clear on that, was he?

The impression I got is that he wants to use one generator as an alternate power source connected to two service-supplied systems via an ATS for each system... but now I'm unsure :cool:
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That is what I thought as well.
 
Smart $ said:
He wasn't real clear on that, was he?

The impression I got is that he wants to use one generator as an alternate power source connected to two service-supplied systems via an ATS for each system... but now I'm unsure :cool:
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Twinman PMed me with what he wants to do, I think. We all need to be on same page with terminology. I am sure we can help if we can have a meeting of the minds:grin:
 
Clarification

Clarification

I apologize if I was not clear...

Two adjacent buildings with separate utility services, but same owner. One of the buildings does not have emergency stanby power. The other has full emergency back-up.

A non life safety load motor load is to be connected to the building without emergency power (bldg #1). Careful evaluation of the operational requirements dictate that the equipment requires emergency back-up.

Someone who is familiar with the site conditions suggested the installation of an ATS in blg #1 and connection of the emergency feeder to the genset in blg #2. A start circuit from the ATS would start the generator. It is my understanding that the ATSs do not seek emergency power. If correct, the ATSs in bldg #2 would not change state in the event that the genset starts, but service #2 is operational.

I ask, is it permissible to implement this arrangement? Is the understanding of the operation of ATSs correct?

If instead of connecting to the genset one were to connect to a panel in bldg #2 (full emergency back-up), what are the implications? I realize that the ATS would be connected to two separate services, one of which has emergency standby power.

Would this not have the benefit that the genset would not start unless service #2 fails?

The load feeder from ATS in bldg #1 is to run in existing conduit which is occupied by other branch circuits originating from bldg#1. So, in the event of service #1 failure, all branch circuits will be "dead", but the motor load feeder will be "live". Is this a violation of 700.9?

Thank you for your help and patience.
 
The ATS is located at one building with a utility service. It is supplying the emergency generator power to another building that is supplied by a separate, entirely different utility service? - if so, this is not a permitted nor safe installation.
 
Pierre C Belarge said:
The ATS is located at one building with a utility service. It is supplying the emergency generator power to another building that is supplied by a separate, entirely different utility service? - if so, this is not a permitted nor safe installation.
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I think the following better depicts what he has in mind...

BLDGS12.gif
 
Pierre C Belarge said:
The ATS is located at one building with a utility service. It is supplying the emergency generator power to another building that is supplied by a separate, entirely different utility service? - if so, this is not a permitted nor safe installation.
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I really don't see this as an issue. Electrically is it is the same as supplying the transfer switch from a gererator that is located outside of the building. A second service (I know the generator is not a service) for emergency systems, legally required standby systems and optional standby systems is permitted by 230.2(A)(2), (3), and (4) and a second feeder to a second building is permitted for emergency systems, legally required standby systems and optional standby systems in 225.30(A)(2), (3) and (4). While this exact set up is not specifically permitted by the code rules, it is my opinion that it meets the intent of the code rules and does not present any safety hazard.
What code section would you cite on the red tag?
 
Existing conduit

Existing conduit

Don,

Let's say that the connection of the emergency feed for ATS in bldg#1 as depicted is permitted. What are the implications of runing the new feeder in existing infrastructure occupied by branch circuits w/o back-up power?

If violation of 700.9, then the only option is to install an ATS and genset by the new load since the existing infrastructure must be utilized. Please advise.
 
don_resqcapt19 said:
I really don't see this as an issue. Electrically is it is the same as supplying the transfer switch from a gererator that is located outside of the building. A second service (I know the generator is not a service) for emergency systems, legally required standby systems and optional standby systems is permitted by 230.2(A)(2), (3), and (4) and a second feeder to a second building is permitted for emergency systems, legally required standby systems and optional standby systems in 225.30(A)(2), (3) and (4). While this exact set up is not specifically permitted by the code rules, it is my opinion that it meets the intent of the code rules and does not present any safety hazard.
What code section would you cite on the red tag?
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Power in building #1 is interrupted. The generator kicks on and supplies building/utility #2.

What interrupts the utility power to building #2?


My issue would be with 225.30
I do not know what I am missing that you see differently, but this setup looks like major trouble to me if power is lost at Building #1 and not at Building #2.
 
my issue is what method is used to keep generator power and utility power being interconnected at building #2. Your proposed line only shows goimng to MDP-2. Is there a proposed transfer switch there also?
 
Pierre C Belarge said:
Power in building #1 is interrupted. The generator kicks on and supplies building/utility #2.

What interrupts the utility power to building #2?


My issue would be with 225.30
I do not know what I am missing that you see differently, but this setup looks like major trouble to me if power is lost at Building #1 and not at Building #2.
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I don't see an issue. There are transfer switches in each building as I understand the installation. If building one loses power the generator starts and the emergency sides of both transfer swtiches are energized. The switch in building 1 will transfer its load the generator. The switch in building two will not transfer its load. Yes the normal line, emergency line and load connections will all be energized at building 2, but that is not a problem.

Note: the latest drawing seems to indicate that there is only one transfer switch. If that is the case there is an issue with the installation as Pierre said.
 
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twinman said:
Don,

Let's say that the connection of the emergency feed for ATS in bldg#1 as depicted is permitted. What are the implications of runing the new feeder in existing infrastructure occupied by branch circuits w/o back-up power?

If violation of 700.9, then the only option is to install an ATS and genset by the new load since the existing infrastructure must be utilized. Please advise.
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If this is an Article 700 installation, you cannot have other conductors in the same raceway as the emergency system conductors, even if it is not possible for both the emergency and non-emergency conductors to be energized at the same time.
 
Bldg #2 service

Bldg #2 service

Disruption of service #2 could only originate from the utility. Connection to the genset is, I am told, via tie breaker. What I called MDP#2 is actually double ended switchgear.
 
Proposed Load

Proposed Load

Don,

The proposed equipment is a motorized gate. It is to be located at the demarcation between secure and unsecured area in an alternate access point.

As such, I assume that the installation is governed by 702.8 rather than 700.9
Consequentely, emergency and general wiring could occupy the same conduit, etc. Correct?

Thank you.
 
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